Mold for a centrifugal impeller, mold inserts and method for building a centrifugal impeller

Abstract

An aerodynamic vane insert configured to reproduce at least an aerodynamic vane of a finished centrifugal impeller and a method for building a centrifugal impeller for a turbomachine.

What is claimed is: 
     
         1 . An aerodynamic vane insert configured to reproduce at least an aerodynamic vane of a finished centrifugal impeller. 
     
     
         2 . The aerodynamic vane insert of  claim 1 , further comprising at least one of:
 a central region configured to reproduce the aerodynamic vane;   opposite shaped end-regions configured to be associated with end-regions of an adjacent vane insert to form an annular insert; and   a shaped component configured to be associated on an external surface of the aerodynamic vane insert, the shaped components being configured to act against the erosion of a working fluid during the work of the finished centrifugal impeller.   
     
     
         3 . The aerodynamic vane insert of at least  claim 1 , wherein the aerodynamic vane insert comprises a single piece or a plurality of pieces. 
     
     
         4 . The aerodynamic vane insert of  claim 1 , wherein the aerodynamic vane insert comprises at least one of a soluble material, a breakable material, a reformable material, and a solid material that can be extracted in multiple pieces. 
     
     
         5 . A method for building a centrifugal impeller for a turbomachine, the method comprising:
 fabricating an annular insert, the annular insert comprising a plurality of aerodynamic vane inserts; and   reproducing aerodynamic vanes of the finished centrifugal impeller.   
     
     
         6 . The method of  claim 5 , further comprising at least one of:
 associating at least a shaped component on the external surface of each said aerodynamic vane insert before associating at least a fabric element on the external surface of each aerodynamic vane insert;   building a first fabric element configured to be associated around each of the said aerodynamic vane inserts;   building a second fabric element configured to be associated on an upper wall of each said aerodynamic vane inserts and on a lower wall of the adjacent said aerodynamic vane inserts; and   building a third fabric element configured to form continuously a plurality of blades between the aerodynamic vane inserts.